What does Psalm 50:19 mean?

The Judge (Psalm 50:1–7), God Himself, is charging Israel with blatant hypocrisy in worship (Psalm 50:8–9, 16–17). The prior verse noted that the nation tolerated thievery and adultery: two clear violations of the Lord's most basic laws for Israel (Exodus 20:14–15). As the next verse notes, this extends to slander: damaging, untrue claims and rumors about others (Psalm 50:20).

This verse's accusation involves deceptive, hateful, or dishonest speech. A nation saturated in such talk cannot claim to be attuned to their Creator. Proverbs 15:28 says, "The mouth of the wicked pours out evil things." James 3:6 describes the tongue as "a fire, a world of unrighteousness." James also calls the tongue "a restless evil, full of deadly poison" (James 3:8). Further he notes, "With it we bless our Lord and Father, and with it we curse people who are made in the likeness of God" (James 3:9). The apostle Paul knew even Christians are tempted to use speech for evil purposes. He commanded, "Let no corrupting talk come out of your mouths" (Ephesians 4:29). He noted the correct alternative for our speech: "only such as is good for building up, as fits the occasion, that it may give grace to those who hear" (Ephesians 4:29).